High speed document feed

ABSTRACT

An apparatus for the seriatim feeding of documents from a stack at high speeds. A friction feed roller is arranged to move in and out of contact with a stack of documents. As the roller approaches the stack of documents there is little or no relative movement between the roller and a document in a feed direction. On contact with the document, the roller begins to accelerate causing a smooth transition from standing to moving as the document is fed.

Unlted States Patent 11 1 1111 3,815,900

Schulze June 11, 1974 HIGH SPEED DOCUMENT FEED 1,441,271 1/1923 De Escobales 271/118 [75] Inventor: Erwin F. Schulze, Novelty, Oh1o Primary Examiner Evon C. Blunk [73] Assignee: Addressograph-Multigraph Assistant Examiner-Bruce H. Stoner, J1.

Corporation, Cleveland, Ohio Attorney, Agent, or FirmRay S. Pyle [22] Filed: Feb. 2, 1973 [57] ABSTRACT [21] Appl' 328971 An apparatus for the seriatim feeding of documents from a stack at high speeds. A friction feed roller is {52] US. Cl. 271/118 arranged to move in and out of contact with a stack of [51] Int. Cl B65h 3/06 documents. As the roller approaches the stack of doc- [58] Field of Search 271/ l 18, 1 17, 1 14, 1 15, uments there is little or no relative movement between 271/126, 127, 109, 116, 110, 111 the roller and a document in a feed direction. On

contact with the document, the roller begins to accel- [56] References Cited erate causing a smooth transition from standing to UNITED STATES PATENTS moving as the document is fed.

640,368 l/l900 Cross 271/1 1 I 2 Claims, 3 Drawing Figures HIGH SPEED DOCUMENT FEED BACKGROUND OF THE INVENTION This invention relates in general to apparatus for handling documents and more particularly, to the seriatim, high speed feeding of documents.

The use of a friction feed roller in document handling devices is well known. The term friction feed roller is generally meant to imply a cylindrical shaped element mounted for rotation about its central axis having an exterior surface composed of hi-friction material allowing minimum spillage between the surface of the roller and the surface of a document to be fed. In prior art concepts, the roller is either continually turning and moved into contact with a document, or constantly in contact with the documents and periodically activated.

The former of these two concepts results in difficulties due to the speed at which the roller contacts a document. Either more than one document at a time is effected by the moving roller or slippage occurs between the roller and the documents causing inefficient feeding of any documents.

Devices of the latter concept are generally more expensive to manufacture. In order to allow continual contact with a document while feeding only on demand, a clutch is generally incorporated into the roller. The clutch allows rolling contact in one direction and sliding or dragging contact in the other direction. How-' ever, of more importance in this case, they are not meant to function as high speed feeding devices.

SUMMARY OF THE INVENTION Therefore, it is an object of this invention to improve the high speed feeding of documents.

A further object is to feed only one document at a time in a seriatim manner.

Another object of the invention is to cause positive engagement of the first document in a stack without inefficient slippage.

Other objects of the present invention will become apparent through a detailed discussion of the preferred embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the document feeding apparatus.

FIG. 2- is a plan view from the top of the document feeding apparatus.

FIG. 3 is a cross sectional view of the document feeding apparatus taken substantially along the line 3-3, looking in the direction of the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT When a normally moving friction feed roller is lowered onto a stack of documents in a manner to cause the roller to stand still or even practically stand still, the effect as the roller is allowed to accelerate to its normal moving speed is a quick, efficient transfer of one document from the stack.

In FIG. I, a document is positioned on the top of a stack of documents shown generally as 12. A friction feed roller 14 for contacting a document to be fed is permanently attached to a shaft l6. A first gear 18 is also attached to shaft 16. A rocker arm 20 is positioned to support the friction feed roller and the first gear. The

rocker arm 20 is mounted to a support surface 22 for rotation about a mounting pin 24.

The support surface 22 serves to permanently mount the various components of the document handling apparatus. A number of arrangements of the support surface are possible. The support surface may be permanently attached to the frame of the machine which is being used in conjunction with the document handling apparatus. In this case, the stack of documents will have to be arranged to move in the direction of the handling apparatus. This is necessary in order that the first document be in the correct position with respect to the friction feed roller for each feeding of a document.

Another possible arrangement of the support surface allows the entire apparatus to ride the surface of the first document on the stack. Here, the spacing of the friction feed roller with respect to the first document is critical. In this case, the stack of documents would not need to be moved.

Still another arrangement of the support surface results in the positioning of the stack of documents 12 on edge. In this case, the document feeder contacts a document 10 on its side surface. Feeding of the document is edgewise in any of four possible directions. Although this arrangement might prove to be less than acceptable for paper sheet documents, feeding card stock and thicker documents would be particularly advantageous by such an arrangement. This would be a result of shock waves set up in the stack of documents 12 due to the striking of documents by the feeder. These shock waves cause document separation in the stack, a highly desired consequence in document feeding.

The arrangement of the support surface has not been indicated in the accompanying drawings, since this is thought to have no bearing on the inventiveness of this disclosure.

A drive gear 26 is directly attached to a motor shaft 28 of an electrical drive motor, not shown in the Figures. The first gear 18 is positioned to be in constant engagement with the drive gear 26. A second gear 30 is likewise positioned to be in constant engagement with the drive gear 26. The second gear 30 is mounted on a clutch shaft 32 which is permanently mounted in the support surface 22. These three gears 18, 26 and 30 constitute a continuously driven gear drive. The arrows in FIG. 1 are indicative of the direction of movement of these gears in this particular embodiment.

A one revolution clutch 34 is directly coupled to the second gear 30.

When the electrical solenoid 36 is activated, a solenoid clapper 40 is pulled away from the clutch 34 allowing movement. The electrical signal to the solenoid 36 is of short duration so that the clapper 40 is almost immediately returned to its restraining position by a spring means 42. As the clutch 34 continues to turn, the clapper 40 rides on the surface of the clutch until a recessed slot 44 engages the clapper and restrains the clutch movement.

A cam shown generally as 45 is coupled to the one revolution clutch 34 for rotation with the clutch when the electrical solenoid activates the-clutch. The cam 45 has a lobe 46 and an inoperative dwell portion 47. The height of the lobe 46 on the cam 45 determines how far the friction feed roller 14 will move in the direction of the document stack 12, and the shape will determine the point of maximum speed known as the point of inflection. At this point the rocker arm 20 will be moving at maximum speed, and will carry gear 18 around the center of shaft 28 at maximum speed. When gear 18 revolves around gear 26, a counterclockwise drive component is produced. The lobe design and drive speed are coordinated to substantially balance the counterclockwise component against the clockwise drive component of gear 26, and thereby produce a movement of shaft 16 toward the stack 12, but with the roller at a substantially stationary peripheral speed, i.e., no rotation. By design according to objectives, therefore, the cam will cause the friction roller to move to the stack 12 at substantially a static drive condition. Thus, as the follower traverses the remainder of the cam, the rocker arm will drive the the roller into tighter contact with the sheet as the roller begins to rotate, first slowly and then accelerating rapidly to kick the top sheet away with a snap action. I

A cam follower 48 coupled to the rocker arm 20 causes the rocker arm to follow the contour of the cam 45. Since the rocker arm is mounted tothe support surface 22 by way of mounting pin 24, the rocker arm is caused to oscillate about the mounting pin by the cam follower 48 riding the surface of the cam 45.

As the rocker arm rotates about mounting pin 24, the shaft 16 causes the friction feed roller 14 and the first gear 18 to also oscillate about mounting pin 24 in such a way that the first gear moves through an arc while remaining constantly engaged to the drive gear 26. In order that the first gear and the drive gear be maintained in engagement throughout the movement of the rocker arm, a number of factors in the design become important. I

The relative sizesof the gears 18, 26, and 30 of course determine the speed at which the friction feed roller contacts the documents. However, once the speed of the friction feed roller 14 is decided upon, any combination of gear sizes which produce the desired speed may be used. In the preferred embodiment, the three gears are the same size making the friction feed roller angular speed equivalent to the drive motor speed.

Whatever the relative sizes of the gears are to be, the

distance A between the centers of shaft 16 and mount- The distance B between the centers of mounting pin 24 and cam follower'48 is also important. This distance B will determine the up and down movement of the friction feed roller. It may easily be understood that when the distances A and B are identical, the upward movement of the cam follower 48 is equivalent to the downward movement of the roller 14. If the distance A is greater than the distance B, the movement at the roller' 14 is amplified. However, if the distance B is greater than the distance A, the movement atthe roller 14 is deamplified. For the most efficient operation of the device, the distance A should be at least as large as the distance B, but certainly not less. In the preferred embodiment, the distances are substantially equal.

As the arrows in FIG. 1 indicate, in this embodiment the drive gear must turn counterclockwise. With the gears engaged as shown in the figures, the first gear 18 and the second gear 30 must turn clockwise. The direction of rotation of the gears is dictated by the desired direction of document feed. In this embodiment, feeding the documents to the left in FIG. 1 necessitates a counterclockwise rotation of the drive'g'ear 26.

In the operation of the apparatus, an electrical signal is received by the solenoid 36 at the appropriate time. Initially, the cam follower 48 rests on the portion of the cam 45- designated above as the inoperative dwell 47. The energization of this solenoid causes the clapper 40 to release the one revolution clutch 34 causing the cam to turn with the second gear 30. As the cam follower 48 rises onto the cam lobe 46, the rocker arm'20 rotates causing the friction feed roller 14 and first gear 18 to be lowered towards the document stack 12. When the first gear moves downward around the mounting pin 24, which has the same effective center line as the motor shaft 28, engagement with the drive gear 26 is maintained.

Since the driving force of the first gear is turning counterclockwise and the rotation of the shaft 16 is also counterclockwise about the same effective axis, the rotations will cancel to some degree. The degree to which the two rotations cancel is directly dependent upon both the speed of rotation of the shaft 16 about the motor shaft and the speed of rotation of the motor shaft 28. The result of this cancelling of rotations is that the friction feed roller 14 decelerates as the first gear moves through an arc in the direction of the stack of documents 12. This cancellation is due to the direction of the arc, through which the roller 14 and first gear 18 travel, and rotation of the drive gear 26 being identical.

When the cam follower 48 has risen entirely onto the lobe 46 of the cam 45, the rocker arm 20 will'have rotated towards the stack of documents 12 as far as is possible. At this point, the rotations will no longer cancel and the first gear 18 accelerates after the friction feed roller 14 encounters a first document 10 of the stack. The result is a smooth transition of a single documerit from standing on the stack to moving to the left, in the case of the present embodiment.

As stated more fully above, the height and rise of the cam lobe 46 determines the speed with which and the distance through which the friction feed roller travels. The length of the lobe, in terms of the extent of the circular arc is important in that the friction feed roller must be disengaged from the stack of documents before more than one document is effected.

When the cam follower 48 reaches the trailing edge of the cam lobe, a single document has been moved a sufficient distance to encounterthe feed apparatus of a machine being utilized with the document feeder. At this point the friction feed roller is removed from contact with the document stack by the cam follower 48 encountering the trailing edge of the cam lobe.

Since the rocker arm 20 causes the shaft 16 to rotate about the motor shaft 28 in a direction opposite to the rotation of the drive gear 26, the rotations will add. Thus the friction feed roller will accelerate as the cam 45 causes the rocker arm to rotate away from the stack of documents. The friction feed roller will again return to its normal driven speed once the cam follower reaches the inoperative dwell portion 47 of the cam.

What is claimed is:

1. A document handling apparatus for feeding documents from a stack, comprising:

a pivot mount;

an arm swingably mounted on said pivot mount;

5 6 a friction feed roller carried by said arm and movable axis of said driven gear to substantially counteract thereby to a position for contacting a document to the rotational speed of said drive gear as the fricbe ad anced, r to an inactive Position; tion feed roller makes first contact with a docua driven gear carried by said arm; mam to b f d;

means drivingly connecting said feed roller to said whereby, the friction feed roller and the paper to be drlven gear; I d h fed first come into static frictional engagement, to a dljwe royatab y mqmte concnmc sald avoid the skidding and smearing tendencies of a pivot; said drive and driven gears being meshed and moving Contact said gears and their distances between centers being proportioned such that pivotal swing of said 10 Apparatus as defind m Clam l f Sald arm driven gear will maintain the gears in meshed rela 1s a rocker mounted at its center on said pivot mount, tionship. and a primary drive gear carried on the opposite end of means to impart a uniform rotation to said driving said rocker said lf drive gear and Saic! drive gear in a direction to rotate said friction roller in a gear bemg meshed and the dlstance between their cellsh t f di di ti l 5 ters being proportioned such that pivotal swing of said means to pivot said arm about said pivot mount from P y driven gear will maintain the gears in meshed inactive position towards document contacting porelationship.

sition at a speed and in the direction to cause the 

1. A document handling apparatus for feeding documents from a stack, comprising: a pivot mount; an arm swingably mounted on said pivot mount; a friction feed roller carried by said arm and movable thereby to a position for contacting a document to be advanced, or to an inactive position; a driven gear carried by said arm; means drivingly connecting said feed roller to said driven gear; a drive gear rotatably mounted concentric with said pivot; said drive and driven gears being meshed and said gears and their distances between centers being proportioned such that pivotal swing of said driven gear will maintain the gears in meshed relationship; means to impart a uniform rotation to said driving gear in a direction to rotate said friction roller in a sheet feeding direction; means to pivot said arm about said pivot mount from inactive position towards document contacting position at a speed and in the direction to cause the axis of said driven gear to substantially counteract the rotational speed of said drive gear as the friction feed roller makes first contact with a document to be fed; whereby, the friction feed roller and the paper to be fed first come into static frictional engagement, to avoid the skidding and smearing tendencies of a moving contact.
 2. Apparatus as defined in claim 1 in which said arm is a rocker mounted at its center on said pivot mount, and a primary drive gear carried on the opposite end of said rocker arm, said primary drive gear and said drive gear being meshed and the distance between their centers being proportioned such that pivotal swing of said primary driven gear will maintain the gears in meshed relationship. 